The detection of differentially expressed microRNAs from the serum of ovarian cancer patients using a novel real-time PCR platform.
OBJECTIVE
To determine the utility of serum miRNAs as biomarkers for epithelial ovarian cancer.


METHODS
Twenty-eight patients with histologically confirmed epithelial ovarian cancer were identified from a tissue and serum bank. Serum was collected prior to definitive therapy. Fifteen unmatched, healthy controls were used for comparison. Serum was obtained from all patients. RNA was extracted using a derivation of the single step Trizol method. The RNA from 9 cancer specimens was compared to 4 normal specimens with real-time PCR using the TaqMan Array Human MicroRNA panel. Twenty-one miRNAs were differentially expressed between normal and patient serum. Real-time PCR for the 21 individual miRNAs was performed on the remaining 19 cancer specimens and 11 normal specimens.


RESULTS
Eight miRNAs of the original twenty-one were identified that were significantly differentially expressed between cancer and normal specimens using the comparative C(t) method. MiRNAs-21, 92, 93, 126 and 29a were significantly over-expressed in the serum from cancer patients compared to controls (p<.01). MiRNAs-155, 127 and 99b were significantly under-expressed (p<.01). Additionally, miRs-21, 92 and 93 were over-expressed in 3 patients with normal pre-operative CA-125.


CONCLUSIONS
We demonstrate that the extraction of RNA and subsequent identification of miRNAs from the serum of individuals diagnosed with ovarian cancer is feasible. Real-time PCR-based microarray is a novel and practical means to performing high-throughput investigation of serum RNA samples. miRNAs-21, 92 and 93 are known oncogenes with therapeutic and biomarker potential.
Resnick
Kimberly E
KE
Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, The Ohio State University College of Medicine, Columbus, Ohio 43210, USA.
Alder
Hansjuerg
H
Hagan
John P
JP
Richardson
Debra L
DL
Croce
Carlo M
CM
Cohn
David E
DE
D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood* / Q000235:genetics*; D018394:CA-125 Antigen / Q000097:blood; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D035683:MicroRNAs / Q000097:blood*; D008875:Middle Aged; D009367:Neoplasm Staging; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D010051:Ovarian Neoplasms / Q000097:blood* / Q000235:genetics* / Q000473:pathology; D016133:Polymerase Chain Reaction / Q000379:methods*; D012334:RNA, Neoplasm / Q000097:blood*
D014408:Biomarkers, Tumor; D018394:CA-125 Antigen; D035683:MicroRNAs; D012334:RNA, Neoplasm